Begin by lining a (12 cup) muffin tin with foil cupcake liners. Bring cream cheese and Cool Whip to room temperature. In the bowl of your electric mixer, (or with a hand mixer), beat the cream cheese until smooth. Add the sweetener and cocoa powder and beat until light and fluffy. Scrape down the sides of the bowl and beat in the milk.
Drop 1 Oreo cookie into each cupcake liner. Spoon cheesecake filling into a large ziplock bag, cut the tip off a corner of the bag, and squeeze filling down to the cut corner. Squeeze just enough filling into each cupcake liner so filling is equally divided between the 12 cups.
With a spoon, press filling down, smoothing it out evenly in the cupcake liner.
Top with hearts, sprinkles, or topping of choice if desired! Cover muffin tin with foil and pop it into the freezer to chill for 4 hours or overnight. The filling firms up perfectly, while remaining smooth and creamy! (They won’t become frozen!) Serve Chilly!